I ended up having to shorten my gas pedal rod when I put in my 261 in my '50 truck, since it was a 62 block and neither pivot location corresponded to a 216. The easiest way is to go to the hardware store and get a little ball joint that you can thread onto the cut off end of the gas pedal rod. Just use a die to cut threads on the rod and spin the ball joint on to give you a bit of adjustability, and put the end of the ball joint through the bell crank. You may find that you need to bend the rod a bit so it doesn't bind. I had to take some of the bend out of mine so I used a vise to squeeze it flatter. Adjust it so the gas pedal is to the floor stop when the carb throttle is open all the way, and that should take care of it.
